1. Field of the Invention
In general, this invention relates to the elemental analysis of an organic material, such as an organic compound or a group of organic compounds. More specifically, the invention relates to methods for the micro-determination of the elements contained in organic materials, by chromatographic study of the products of combustion of such materials. In particular, the present invention is directed to an improved microanalytical method involving a combined combustion and gas chromatographic technique for the simultaneous determination of the elements, carbon, hydrogen, sulfur, chlorine, bromine, iodine and nitrogen in a single, small sample of an organic material.
2. Description of the Prior Art
Elemental analysis of an organic material is a common type of analytical determination which is performed to identify and obtain other information about the material. The elements typically of interest are carbon, hydrogen, sulfur, nitrogen, chlorine, bromine, iodine and oxygen. In some instances, the element phosphorus may also be of interest. Standard micro-methods not involving gas chromatography are available for use in conducting these elemental analyses, but such methods are very time consuming and complicated.
Since gas chromatography is well suited to the separation and quantification of gaseous compounds in mixtures of gases, efforts heretofore have been made to apply a gas chromatographic analytical technique to the separation and quantification of the gaseous products produced by the combustion or pyrolysis of a small sample of the material to be analyzed. However, for a number of reasons these efforts have not been completely satisfactory. For one thing, they have not provided a system which can perform, on a single, small sample, a complete elemental analysis of all of the elements which commonly are present in a majority or organic compounds. Thus, in U.S. Pat. No. 3,304,159, Hinsvark discloses a gas chromatographic analytical method applicable to the combustion products which are obtained from samples including the elements, carbon, hydrogen and nitrogen. Similarly, a combustion-chromatographic method for the quantitative determination of the elements, carbon, hydrogen, nitrogen and sulfur in organic materials is disclosed by Dugan in U.S. Pat. No. 3,838,969. However, heretofore there has been no method which would permit of the microanalytical determination, utilizing a combustion-chromatographic technique, of the elements, carbon, hydrogen, sulfur, chlorine, bromine, iodine and nitrogen from a single, small sample.